Environment of the United States

Because of the strong forces of economic exploitation and industrialization, humans have had deep effects on the ecosystems of the United States, resulting in a number of environmental issues.

These movements are intertwined with a long history of conservation, starting in the early 19th century, that has resulted in a robust network of protected areas, including 28.8% of land managed by the Federal government.

The country has more than 17,000 identified native species of flora, including 5,000 in California (home to the tallest, the most massive, and the oldest trees in the world).

The country's ecosystems include thousands of non-native exotic species that often harm indigenous communities of living things.

Following World War II, cities in the southern and western region experienced an economic and population boom.

[9][10] The term "conservation" appeared in 1908 and was gradually replaced by "environmentalism" in the 1970s as the focus shifted from managing and protecting natural resources to a broader concern for the environment as a whole and the negative impact of poor air or water on humans.

[24][25][26] Climate change's impacts on tropical cyclones and sea level rise also affect regions of the country.

Cumulatively since 1850, the U.S. has emitted a larger share than any country of the greenhouse gases causing current climate change, with some 20% of the global total of carbon dioxide alone.

[28] Various state and federal climate change policies have been introduced, and the US has ratified the Paris Agreement despite temporarily withdrawing.

This includes implications for agriculture, the economy (especially the affordability and availability of insurance), human health, and indigenous peoples, and it is seen as a national security threat.

[31] US States that emit more carbon dioxide per person and introduce policies to oppose climate action are generally experiencing greater impacts.

[32][33] 2020 was a historic year for billion-dollar weather and climate disasters in U.S.[34] Conservation in the United States can be traced back to the 19th century with the formation of the first National Park.

The United States is part of North America .
Bioregions of Northern America, according to one scheme.
Köppen climate types of the US
Shaded relief map of the United States, showing 10 geological provinces
Trends in carbon dioxide emission in US, 1800 to 2020
United States National Marine Sanctuaries
Of the major greenhouse gas emitting nations, the U.S. is among the highest per person emitters. [ 14 ]
Annual CO 2 emissions, total by country (2017 data) shows the U.S. trails China in total annual emissions (not per capita ).
Average temperatures in almost all regions in the U.S. have increased in the last 120 years. [ 18 ]
Annual temperatures averaged across the U.S. have exceeded the 1971–2000 average almost every year in the 21st century. [ 19 ]
Yosemite National Park